What to do if another photographer is blocking your view?

[TheBlackGrouse]

Ok, some problems finding out what really happened, but a good question, looking at all the reactions. Some hidden anger is coming up, I totally understand, there are more or less the same problems when photographing wildlife. Photographers who jump over a fence while others stay behind and try not to disturb anything. By the way, just an example, I'm not comparing the OP with them ;-)